Source for 7 pin mic inserts?

[Khron]

Right right. I see what you mean now- it’s about easily cannibalising them for the insert.

... With minimal (or in this case, no) "tuning" necessary.

 

[Khron]

Oh, by the way - came across a much cheaper option for an insert-donor:

https://www.tme.eu/fi/en/details/fc6185/xlr-connectors/cliff/
And you could probably mount the stock BM800 3-pin insert in there and still have a usable panel-mount connector